Optical networks are becoming prevalent in part because service providers want to deliver high bandwidth communication capabilities to customers. FIG. 1 illustrates a fiber optic network 100 deploying passive fiber optic lines. As shown in FIG. 1, the network 100 may include a central office 110 that connects a number of end subscribers 115 (also called end users 115 herein) in a network. The central office 110 may additionally connect to a larger network such as the Internet (not shown) and a public switched telephone network (PSTN). The network 100 may also include fiber distribution hubs (FDHs) 130 having one or more optical splitters (e.g., 1-to-8 splitters, 1-to-16 splitters, or 1-to-32 splitters) that generate a number of individual fibers that may lead to the premises of an end user 115. The various lines of the network can be aerial or housed within underground conduits (e.g., see conduit 105).
The portion of network 100 that is closest to central office 110 is generally referred to as the F1 region, where F1 is the “feeder fiber” or “feeder distribution cable” from the central office. The F1 portion of the network may include an F1 distribution cable having on the order of 12 to 48 feeder fibers; however, alternative implementations may include fewer or more fibers. The portion of network 100 near the end users 115 may be referred to as an F2 portion of network 100. Splitters used in an FDH 130 may accept fibers from an F1 distribution cable and may split those incoming fibers into, for example, 216 to 432 individual distribution fibers that may be associated with one or more F2 distribution cables. The F2 distribution cables are routed in fairly close proximity to the subscriber locations. Each fiber within the F2 distribution cable is adapted to correspond to a separate end user location.
Referring to FIG. 1, the network 100 includes a plurality of breakout locations 125 at which branch cables (e.g., drop cables, stub cables, etc.) are separated out from main cables (e.g., distribution cables). Breakout locations can also be referred to as tap locations or branch locations and branch cables can also be referred to as breakout cables. At a breakout location, fibers of the branch cables are typically spliced to selected fibers of the main cable. However, for certain applications, the interface between the fibers of the main cable and the fibers of the branch cables can be connectorized.
Stub cables are typically branch cables that are routed from breakout locations to intermediate access locations 104 such as a pedestals, drop terminals or hubs. Intermediate access locations 104 can provide connector interfaces located between breakout locations and subscriber locations. A drop cable is a cable that typically forms the last leg to a subscriber location 115. For example, drop cables are routed from intermediate access locations 104 to subscriber locations 115. Drop cables can also be routed directly from breakout locations 125 to subscriber locations 115 hereby bypassing any intermediate access locations.
Branch cables can manually be separated out from a main cable in the field using field splices. Field splices are typically housed within sealed splice enclosures. Manual splicing in the field is time consuming and expensive.
As an alternative to manual splicing in the field, pre-terminated cable systems have been developed. Pre-terminated cable systems include factory integrated breakout locations manufactured at predetermined positions along the length of a main cable (e.g., see U.S. Pat. Nos. 4,961,623; 5,125,060; and 5,210,812).